1. Field of the Invention
This invention relates in general to high pressure actuating devices for chokes and valves and, more particularly, to an automatic choke or valve positioning control system having manual override capability.
2. Background
The invention, a stepping actuator with electromechanical feedback control system, is used for precise positioning of a choke device in a high pressure flowline such as from an oil or gas well.
Various types of choke devices have been used to control the flow rate from a high pressure production line and to reduce the downstream pressure to safe and convenient levels. Provision for remote and manual control is oftentimes desirable and is sometimes provided for such devices. However, the degree of precision control and the reliability of the known devices have been found wanting. In addition, very large devices for providing very large torques have heretofore been necessary.
It is therefore an object of the invention to provide a stepping actuator with a simple gear drive of few parts to minimize backlash and increase control precision.
Another object is to provide a stepping actuator with an electro-mechanical feedback control system with automatic remote control and manual override capabilities.
A further object is to provide a stepping actuator having a gear drive which operates with minimal torque requirements.